The present disclosure relates generally to semiconductor devices, and more specifically to integrated circuits (ICs) and fabrication methods thereof.
The semiconductor integrated circuit (IC) industry has experienced rapid growth. Technological advances in IC materials and design have produced generations of ICs where each generation has smaller and more complex circuits than the previous generation. To enhance the performance of ICs, strained silicon has been used to enhance carrier mobility and improve device performance. Strained silicon is a layer of silicon in which the silicon atoms are stretched beyond their normal interatomic distance. Moving these silicon atoms farther apart reduces the atomic forces that interfere with the movement of electrons through the transistors and thus better mobility, resulting in better chip performance and lower energy consumption.